May in Ust'-Kem' is the windiest month of the year. In May, the weather in Ust'-Kem' is typically warm. Average daily high temperature in May is about 11 degrees above zero. On average, Ust'-Kem' has 14 rainy, 12 cloudy, 3 sunny, and 2 partly cloudy days in May. The rains are usually moderate. May as well as January, February, April, and September is considered the most uncomfortable time to visit Ust'-Kem'.